Massive clippy breakage incoming

[oli-obk]

When rust-lang/rust#50050 (comment) is implemented, we lose all ability to detect macro expansions.

No ETA on getting them back, but there's a plan outlined in the link above.

[phansch]

Won't that also break some rustc lints?

Once that's on nightly, we should probably put the last working nightly/clippy version combination at the top of the readme, as #2705 suggests.

[phansch]

@oli-obk I think this will be fully fixed by using in_external_macro from rust-lang/rust#52467, right?

[oli-obk]

Probably. I think we'll see some changes in tests

[phansch]

IIRC this breakage didn't turn out too bad, so I'm going to close this issue.